A conventionally known photomultiplier tube has a configuration that electrons emitted from a photocathode provided on a side of a vacuum vessel are multiplied by dynodes and then detected by anodes, and that stem pins are connected to respective ones of dynodes and anodes and installed to a stem so that the stem pins can be a guide from inside of the vacuum vessel to outside thereof. In one of such photomultiplier tubes, stem pins are individually fixed to a metallic stem respectively via tapered hermetic glass. Another one of such photomultiplier tubes includes stem pins individually and directly fixed to a large tapered stem made of hermetic glass (for example, refer to patent document 1). There is another known photomultiplier tube in which a dish-shaped stem metallic plate is provided such that the dish-shaped stem metallic plate can surround an outer surface of a stem constituting another end of the vacuum vessel, and the stem is formed by filling glass into the stem metallic plate (for example, refer to patent document 2).
Patent document 1: Japanese Patent Application Publication No. H5-290793 (pages 3-4, FIGS. 1 and 7)
Patent document 2: Japanese Patent Application Publication No. 2005-11592 (page 3, FIG. 1)